In the link below is a story from New Zealander Mike Holland, who spent winter in Bali and fortunately took a Zephyr with him.
ozonekites.com/water?source=rssfeedI've ridden the 2011 Zephyr heaps, love it. Does not feel or handle like a big truck, more like a nimble VW van :-)
I've seen wdric at our races series several times with the Turbine, he does well on it and I think he weighs in about 85kg after cabling.
Turbine is stable too never seen it luff or misbehave, I think the Zephyr relaunches easier and has a bigger top end, with equal or better bottom end. Pick either, you would not be disappointed.